What are Mysimba obesity treatment pros and cons ?

Mysimba is a diet pill developed by Orexigen Therapeutics in the US. It is used for weight loss treatment and is considered an adjunct therapy along with diet and exercise. It is available under two brand names:

  • Contrave
  • Mysimba

Approved by the Food and Drug Administration (FDA), Mysimba is a combination of two drugs:

  • Bupropion
  • Naltrexone

Both of these drugs have long been in use individually. Bupropion is used as an antidepressant and smoking cessation drug. Whereas, Naltrexone is an anti-addiction drug.


Mysimba obesity control treatment is for the weight loss treatment in the adults who are ≥18 years old. Indications are as follows:

  • Obese adults who have BMI (body-mass-index) ≥ 30 kg/m2
  • Overweight adults who have BMI of ≥ 27 kg/m2 and < 30 kg/m2 with at least one weight-related complication such as dyslipidemia, high blood pressure, or type 2 diabetes.

Body-mass-index (BMI) is an indication of body weight in relation to the height of a person.


Mysimba is available in the form of prolonged-release tablets. It contains:

  • 2 mg naltrexone
  • 78 mg bupropion

Prolonged-release means that the drug is released slowly over the next few hours of intake. It cannot be obtained without the prescription of a doctor. However, one can buy Mysimba online through an online prescription system.


The initial dosage for Mysimba obesity treatment is one tablet each morning. Over the duration of the next four weeks, it is then gradually increased to two tablets twice a day. It is preferable to take medicine with food. The use is specifically for weight loss.

Mechanism of action:

The exact mechanism of action of Mysimba obesity treatment is unknown. It is, however, known that Bupropion increases the dopamine levels in the brain. Dopamine reduces the appetite along with more energy expenditure by the body. This helps in weight loss.

Naltrexone makes certain types of foods such as sweet items less palatable. Both components of Mysimba reduce the pleasure associated with eating. This helps the patient to stick to a low-calorie diet, ultimately helping in weight loss.

It has been seen in the past that patients taking Bupropion as anti-depressant had weight loss. This weight loss, however, discontinued after the treatment.


The results from clinical trials show the effectiveness of Mysimba obesity treatment as follows:

  • After 16 weeks of therapy, 50.8% of the users lost > 5% of the body weight.
  • After one year, 55% of the users among the same 50.8% of the people who lost weight in 16 weeks, lost more than 10% of the body weight. Average weight loss in one year was 11.3%.
  • There were better treatment effects in the patients who completed 56 weeks of treatment, or who had lost at least 5% of their original body weight by the 16th week.

When to stop the treatment?

Treatment should be discontinued if there is not a weight loss of at least 5 percent of the initial body weight after 16 weeks of treatment. It should also be stopped in the presence of severe side effects such as high blood pressure.

Mysimba obesity treatment pros:

Not only weight loss, but Mysimba obesity treatment also reduces the risk of weigh-associated diabetes and cardiovascular diseases. There is a reduction in the triglycerides and LDL cholesterol, which is the bad cholesterol. Better glycemic control in diabetic patients has also been observed in research studies.

Mysimba obesity treatment cons:

There are certain side effects and contraindications for this treatment. Mysimba side effects occur in more than 1 out of 10 people.

Most common side effects are as follows:

  • Nausea
  • Vomiting
  • Constipation
  • Dizziness
  • Dry mouth
  • Pain in the abdomen
  • Headache
  • Difficulty in sleeping

Other side effects:

  • Anxiety
  • Agitation
  • Joint and muscle pain.


It is contraindicated in case of hypersensitivity to any of its constituents. Other cases of contraindications are as follows:

  • Compromised kidney or liver functions.
  • Uncontrolled high blood pressure.
  • Seizure disorders.
  • Brain tumor.
  • History of bipolar disorder.
  • Patients having withdrawal effects of benzodiazepines and alcohol.
  • Ongoing treatment with drugs containing bupropion or naltrexone.
  • Current and past cases of bulimia and anorexia nervosa.
  • Patients taking opioid drugs.
  • Current monoamine oxidase inhibitors (MAOI) use or a use in the past 2
  • Abrupt discontinuation of drugs like barbiturates, and antiepileptic.

Special Warnings and Precautions for Use:

Special precautions need to be taken while undergoing Mysimba obesity treatment. The following conditions need immediate medical consultation:


Mysimba should be discontinued in patients who experience seizures during treatment. Bupropion is associated with a dose-related risk of seizures. Patient factor, drugs in use, and clinical situations should be considered prior to prescribing the drug. People who have predisposing seizure factors should be prescribed the drug with caution and close monitoring.


Consumption of alcohol during Mysimba treatment should be avoided.

Allergic reactions:

Bupropion intake has reported incidents of anaphylactic shock, erythema multiform and Stevens-Johnson syndrome. Mysimba use should be immediately discontinued if any of the following symptoms are seen:

  • Swelling of the lips, tongue, throat or face
  • Difficulty in swallowing or breathing
  • Dizziness
  • Fever
  • Pain in the joints and muscles
  • Itching or hives
  • Rash

Suicidal behavior:

Close monitoring of young patients receiving Mysimba obesity treatment is required. Patients should be monitored for any change in behavior and suicidal tendencies.

Elevation of blood pressure:

Bupropion contains drug combinations have been associated with high blood pressure. The cautious prescription is advised for the patients of controlled hypertension. If there are any signs of high pulse or high blood pressure, discontinue the treatment and consult your doctor.

Cardiovascular disease:

Caution should be practiced while prescribing Mysimba to the patients who have active coronary artery disease or any history of cerebrovascular incidents. The safety of this drug in relation to history of recent myocardial infarction or other unstable heart disease has not been established on a clinical level.

Elderly patients:

It is not recommended for patients over 75 years of age.

Renal impairment:

Patients with moderate renal or hepatic impairment should not be prescribed Mysimba.

Pregnancy and Breastfeeding:

Mysimba treatment is not recommended for pregnant women and those who are attempting to become pregnant or during breastfeeding.

Children and Adolescents:

Mysimba should not be used in children and adolescents below 18 years.

Buy Mysimba online:

You can not currently buy Mysimba online even after the prescription of the doctor.

There seem to be no official pharmacies that sell it.


Warning: The drug is dangerous for use in certain clinical conditions. Consult your doctor for a prescription of this drug.